modules: add documentation for module sourcesets
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-22-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/docs/devel/build-system.rst b/docs/devel/build-system.rst
index 7ef36f4..fd16504 100644
--- a/docs/devel/build-system.rst
+++ b/docs/devel/build-system.rst
@@ -272,6 +272,23 @@
target_arch += {'arm': arm_ss}
target_softmmu_arch += {'arm': arm_softmmu_ss}
+Module sourcesets:
+ There are two dictionaries for modules: `modules` is used for
+ target-independent modules and `target_modules` is used for
+ target-dependent modules. When modules are disabled the `module`
+ source sets are added to `softmmu_ss` and the `target_modules`
+ source sets are added to `specific_ss`.
+
+ Both dictionaries are nested. One dictionary is created per
+ subdirectory, and these per-subdirectory dictionaries are added to
+ the toplevel dictionaries. For example::
+
+ hw_display_modules = {}
+ qxl_ss = ss.source_set()
+ ...
+ hw_display_modules += { 'qxl': qxl_ss }
+ modules += { 'hw-display': hw_display_modules }
+
Utility sourcesets:
All binaries link with a static library `libqemuutil.a`. This library
is built from several sourcesets; most of them however host generated
